Lock bottom box



Feb. 22, 1955 J H CRAWFORD 2,702,662

LOCK BOTTOM BOX Filed Oct. 26, 1951 A I 15 1 Z7 Z5, [Z7VEZ77.Z":/ James fiz azgfozd United States Patent LOCK BOTTOM BOX James H. Crawford, Fort Wayne, Ind., assignor to Fort Wayne Corrugated Paper Company, Fort Wayne, Ind., a corporation of Indiana Application October 26, 1951, Serial No. 253,258

1 Claim. (Cl. 22916) This invention relates to a lock-bottom box, or container, having double thickness side and bottom walls.

In my copending application Serial No. 247,433, filed September 20, 1951, l have disclosed a lock-bottom type of box wherein the bottom wall and two, only, of the side walls are of double thickness. For some purposes, however, it is desirable to have all of the side walls of double thickness, and this is accomplished by the present invention. Thus, the box, or container, of my present invention provides all of the advantages of a lockbottorn type and also the advantages of a double wall thickness for not only the bottom wall but also for all of the side walls.

It is therefore an important object of my invention to provide a novel and improved lock-bottom type of box having double wall thicknesses throughout.

Other and further important objects of this invention become apparent from the following description and appended claim.

On the drawings:

Figure l is a perspective view of the assembled container of my invention, with its bottom wall uppermost and with the box open at its lower side.

Figure 2 is a top plan view of the box looking into the open top of the box.

Figure 3 is a sectional view taken substantially along the line III-HI of Figure 2.

Figure 4 is a sectional view taken substantially along the line IV--IV of Figure 2.

Figure 5 is a plan view of the blank from which the box of my invention is formed, showing in dotted lines the crease or score lines for facilitating folding into the assembled position.

As shown in the drawings:

The box, indicated generally by the reference numeral 10, comprises a section that is rectangular in shape. It is contemplated that two box sections may be assembled with an inner lining, as illustrated in my copending application above referred to, to form a closed container, or that two box sections like the section 10, but with one smaller than the other, may be assembled by telescoping one within the other to form a closed container.

Each box-like section is formed from an identical blank, such as the blank 11 illustrated in Figure 5. In the form there shown, the blank 11 comprises a plurality of rectangularly shaped panels so arranged and separated, or connected by score lines, as to be capable of being folded and set up into the form of the box section 10. The blank 11 comprises a series of panels 12, 13, 14 and arranged in a continuous strip, with the panels 12 and 13 joined by a score line 16, the panels 13 and 14 joined by a score line 17, and with the panels 14 and 15 joined by a score line 18. The panel 12 is further joined, by a score line 19, to an end flap 20. The flap 20, as will later be explained, is stapled to the free end, as at 21, of the panel 15, when the box is assembled. The panels 12, 13, 14 and 15 are all of the same width but may be of ditferent lengths, provided that the panels 12 and 14 are of equal length and the panels 13 and 15 are of equal length, since these pairs of panels coact, respectively, in forming the side walls of the box. As will be later pointed out, the panels 12 and 14 constitute one set of outer side walls, while the panels 13 and 15 cooperate to form another set of outer side walls.

In the next row of panels, lying adjacent to the row ice just described, there is a panel 22 joined by a score line 23 to the panel 12, and a panel 24 joined by a score line 25 to the panel 14. The panel 22, when the box is assembled, constitutes an inner bottom wall, while the panel 24 constitutes the outer bottom wall. Attached laterally to the panel 24 by score lines 26 and 27 are panels 28 and 29, respectively. Said panels 28 and 29 are of substantially the same dimensions and constitute inner side walls that mate, respectively, with the outer side walls 13 and 15. In order to permit assembly, the panel 28 is separated from the panel 13 by a line of severance 30, while the panel 29 is separated from the panel 15 by a similar severance line 31. The severance lines 30 and 31 are continuations of the score line 25. In order to prevent binding of the panels during assembly, the score lines 26 and 27 are slightly ofiset inwardly of the corresponding score lines 17 and 18, and the severance lines 30 and 31 extend, respectively, to the ends of the score lines 26 and 27.

In the third, or uppermost row of panels shown in Figure 5, there is a panel 32 joined by a score line 33 to the panel 22; a panel 34 joined by a score line 35 to the panel 28; and a panel 36 joined by a score line 37 to the panel 29. The panel 32, when the box is assembled, is adapted to lie against the inside of the panel 14 to form therewith a double-walled side of the box. Accordingly, the panel 32 is of substantially the same dimensions as the panel 14. The panels 34 and 36, when the box is assembled, cooperate to form an inner side wall that lies against the side wall panel 12 to form a side wall of double thickness. Each of the side walls 34 and 36, has an area substantially one-half that of the area of the side wall panel 12, so that when the panels 34 and 36 are in position, with their edges 38 and 39v adjacent each other, their combined area is substantially coextensive with the area of the panel 12. It will be noticed that the free inner edges (as viewed in Figure 5) of the panels 34 and 36, indicated by the reference numerals 40 and 41, respectively, are offset slightly from the score lines 26 and 27. This ofisetting is for the purposes of preventing binding during the act of assembling.

In describing the assembly of the blank 11 into the box section 10, it will be assumed that the outer bottom panel 24 remains in its initial plane, which may suitably be a horizontal plane in contact with a supporting surface. With the panel 24 held fixedly in a horizontal plane, the panel 28 is first raised about the score line 26 into vertical position. This also raises the panel 34 to vertical position. Next, the entire strip constituted by the panels 12, 13, 14 and 15, is raised into vertical position about the score lines 23 and 25. With this strip in vertical position, and with the score line 17 as a vertical hinge, the panels 32 and 22 are swung in a horizontal plane through a full 180 over the surfaces of the panels 36, 29 and 24. The panel 32 is bent up into vertical position about the score line 33 toward the end of this operation so as to lie against and inside of the panel 14 when the operation is completed. Also, toward the end of this same operation and as soon as the panel 32 has passed over and beyond the panel 36, said panel 36 is raised into vertical position about the score line 37 so as to lie inside of the panel 12 and also inside of the flap 20. As the panel 36 is being raised, the panel 29 is also raised toward vertical position about the score line 27, and during such movement, the panel 36 is swung through to lie inside of the panel 12 and to form with the panel 34 an inside wall against said panel 12, the edges 38 and 39 then being in vertical position and substantially abutting each other. The flap 20 is next folded to be against the margin of the panel 29 and finally the panel 15 is swung around the score line 18 as a vertical pivot until the panel 15 lies outside of and against said flap 20. The flap 20 is secured in place by means of staples 42, or the like, ex tending through the marginal edge 21 of the panel 15 and thickness of the flap 20, but not necessarily through the inner panel 29.

As illustrated in Figures 1 to 4, inclusive, the assembled box section 10 comprises a double-thickness bottom wall consisting of the outer bottom wall panel 24 and the inner bottom wall panel 22; a first double-thickness side wall consisting of the outer side wall panel 12 and the inner two-piece side wall 34, 36; a second doublethickness side wall consisting of the outer side wall panel 13 and the inner side wall panel 28; a third double-thickness side wall consisting of the outer side wall panel 14 and the inner side wall panel 32; and a fourth doublethickness side wall consisting of the outer side wall 15 and the inner side wall panel 29. Thus, all of the five walls of the open-sided box section are of doublethickness. The material of the blank is preferably faced, corrugated board, but may be any type of fiber board, card board or the like.

Furthermore, due to the construction just described, the box section 10 is of the lock-bottom type. This follows from the fact that the inner bottom wall panel 22 is both integrally connected through the score line 23 with the side wall panel 12 and to the inner side wall panel 32 by the score line 33, yet the inner bottom panel 22 lies above the outer bottom panel 24 and is held thereagainst by the two-part inner side wall panels 34, 36. Thus, when the flap 20 is stapled between the marginal portion 21 of the outer side wall panel and the corresponding mar ginal portion of the inner side wall panel 29, the inner and outer bottom wall panels 22 and 24 are securely locked together and in place, without the necessity of gluing said bottom wall panels 22 and 24 together or otherwise directly uniting them. A very strong, rigid construction results from this relationship between the various panels in the assembled condition of the box.

As previously stated, if it is desired to make a closed container from two similar box sections, one is made somewhat smaller than the other so as to fit within the larger box section. The double-thickness bottom wall of one box section constitutes the bottom of the closed container, while the other double-thickness bottom wall constitutes the top wall of the assembled container. Alternatively, as is shown in my copending application referred to above, similar box sections 10 may be used as the end closures for an open-ended inner liner. In either case, all of the walls are of at least double thickness and therefore comparatively rigid and strong, so as to be capable of bearing heavy loads.

It will be understood that modifications and variations may be effected without departing from the scope of the novel concepts of the present invention.

1 claim as my invention:

A lock-bottom box comprising a continuous outer side wall of articulated first, second, third and fourth outer side wall panels with the initially free edges of the first and fourth panels permanently joined together, an outer bottom wall bent from the bottom edge of the third side wall panel, a pair of inner side walls bent upwardly from opposite ends of said outer bottom wall and lying against the inner faces of the second and fourth panels, an inner bottom wall bent from the bottom edge of said first outer side wall and overlying said outer bottom wall, an inner side wall bent from that edge of said inner bottom wall opposite said first outer side wall and lying against the inner face of said third outer side wall panel, and other smaller inner side walls bent respectively from vertical edges of said pair of inner side walls and lying against saiclll first outer wall and together being coextensive therewit References Cited in the file of this patent UNITED STATES PATENTS 640,818 Schnackenberg Jan. 9, 1900 736,955 Garman Aug. 25, 1903 1,152,844 Rexford Sept. 7, 1915 r 1,200,522 Richardson Oct. 10, 1916 1,493,460 Pinkerton May 6, 1924 1,506,208 Webb Aug. 26, 1924 1,828,448 Seidel Oct. 20, 1931 2,418,963 Anderson Apr. 15, 1947 2,518,818 Ringler Aug. 15, 1950 2,577,588 Paige Dec. 4, 1951 

